In an ultrasonic imaging apparatus, an apodization parameter is necessary to beamforming. For the majority of ultrasonic imaging systems, the apodization parameter is calculated in advance and stored in hardware storage. Since the apodization parameter is a quantity varying with the depth variation of the received beam, and is further relevant to the position of the reception ray in linear array trapezoid scanning and phase-controlled matrix scan. Therefore the total number of those apodization parameters may be up to tens of Mbits or more. Thus this will cause the increasing of extra memory devices of the system, as well as the cost thereof. Furthermore, the time needed to load new parameters when a probe is switched will also be relatively longer, and thus causing the use of the apparatus to be inconvenient.
The U.S. Pat. No. 6,123,671 discloses a method for reading corresponding apodization values from pre-stored apodization parameters by different transducer elements, but does not relate to real time calculation of apodization parameters. The solution of U.S. Pat. No. 6,123,671 still needs relatively large amount of memory space because stored apodization parameters are relevant to the depths, and is suitable for perpendicular transmitting of convex matrix and linear matrix, therefore is relatively restricted.
The real time parameter calculation with hardware is a possible solution. A scanning line is taken as a basic unit of ultrasonic imaging. Only a few number of parameters are required to be pre-stored, and only several control parameters are required to be written before the transmitting/receiving of each scanning line, required apodization parameters can be automatically generated by the hardware during the reception, thereby the memory resources of the system can be greatly saved.